Abstract: Passive pressure sensors for use in a shunt valve system or other intracranial implants, for measurement of intracranial pressure of cerebrospinal fluid within the brain cavity. Such a pressure sensor implant can be very simple, e.g., including only a micro-membrane configured as a diaphragm, formed of a biocompatible polymer or other material (e.g., PMMA, PDMS, PEEK, polyimide or a biocompatible hydrogel), and an associated air cavity, without any required electronic components. The diaphragm, or air cavity are configured to exhibit changes in response to changes in CSF pressure, which can be detected through ultrasound readout. Ultrasound query at specific frequencies can be used to track such changes which can be correlated to intracranial pressure. Such an ultrasound readout is completely remote, taken from outside the patient's body, without requiring any electronics, wires, etc. for connection to the implant.

Abstract: A power transfer-based flexible sensing platform that can be used in a fluid environment includes at least one metallic thin film structure, with a polymeric encapsulation that protects the metallic thin film structure from the fluid environment, a smart hydrogel sandwiched between layers of the metallic thin film structure, the smart hydrogel being configured to swell or shrink in response to stimulus, and an AC power source or signal generator electrically connected to the at least one metallic film structure. The metallic thin film can include first and second U-shaped metallic thin film structures, each encapsulated, where the smart hydrogel is sandwiched between them. An AC power or signal source is electrically connected to one of the U-shaped structures, causing power to be inductively transferred to the other. Measurement of the induced power or other signal can be used to determine a concentration of an analyte in the fluid environment.

Abstract: A transition microelectrode (108) can include a micro well array (104) having a plurality of microwells. The transition microelectrode (108) can further include a plurality of neuronal soma oriented within the plurality of microwells. A bioerodible probe guide (106) can be oriented over the microwell array (104). An electrode (103) can be electrically connected with the plurality of microwells. A transition microelectrode array (116) can include an electrode array having a plurality of the transition microelectrodes (108).

Abstract: Systems and methods for accurately measuring changes in biomarker sensitive hydrogel volume and shape due to exposure to various biomarkers include a system for identifying one or more dimensional changes in a biomarker sensitive hydrogel positioned within an in vivo environment. The system includes a biomarker sensitive hydrogel positioned within an in vivo environment and configured to dimensionally change in response to interaction with predefined biomarkers. The system additionally includes an ultrasound transducer for locating and identifying one or more characteristics of the biomarker sensitive hydrogel and a computer system in electrical communication with the ultrasound transducer. The computer system is configured to receive characteristics of the biomarker sensitive hydrogel from the ultrasound transducer and determine dimensional changes of the biomarker sensitive hydrogel based on the received characteristics.

Abstract: Microresonator structures including a top polymer film layer, a bottom polymer film layer, and a smart hydrogel structure sandwiched between the polymer film layers. An ultrasound resonator cavity having a resonance frequency is defined between the top and bottom polymer layers, and the smart hydrogel structure is configured to provide a change in height to the ultrasound resonator cavity due to volumetric expansion or contraction of the smart hydrogel structure, in response to interaction of the smart hydrogel structure with one or more predefined analytes in an in vivo or other environment. Related methods of use for determining the presence or concentration of a given target analyte, as well as methods of fabricating such microresonator structures are also described.

Abstract: Systems and methods for measuring changes in smart hydrogel microresonator structures positioned in an in vivo or other environment, having an acoustic resonance frequency in an ultrasound range. The system includes a smart hydrogel microresonator structure positioned within the environment configured to exhibit a change in resonance frequency in response to interaction with one or more predefined analytes in the environment. The system includes an ultrasound transducer for querying the smart hydrogel microresonator structure at or near its resonance frequency. The system also includes a computer system configured to receive ultrasound data as provided by query of the smart hydrogel microresonator structure and to determine changes in resonance frequency, amplitude or intensity of the ultrasound query wave, or mean grayscale value (MGV) associated with the ultrasound data of the smart hydrogel microresonator structure due to the change in resonance frequency.

Abstract: Microfluidics sensor devices having an array of smart polymer hydrogel features for resistive channel analyte sensing via hydrogel swelling and de-swelling, and methods of manufacturing and using the same. Inexpensive, rapid-responsive, point-of-use sensors for monitoring disease biomarkers or environmental contaminants in, for example, drinking water, employ smart polymer hydrogels as recognition elements that can be tailored to detect almost any target analyte. Fabrication involves mask-templated UV photopolymerization to produce an array of smart hydrogel pillars, with large surface area-to-volume ratios, inside sub-millimeter channels located on microfluidics devices. The pillars swell or shrink upon contact aqueous solutions containing a target analyte, thereby changing the resistance of the microfluidic channel to ionic current flow when a bias voltage is applied to the system. Hence resistance measurements can be used to transduce hydrogel swelling changes into electrical signals.

Abstract: Systems and methods for accurately measuring changes in biomarker sensitive hydrogel volume and shape due to exposure to various biomarkers include a system for identifying one or more dimensional changes in a biomarker sensitive hydrogel positioned within an in vivo environment. The system includes a biomarker sensitive hydrogel positioned within an in vivo environment and configured to dimensionally change in response to interaction with predefined biomarkers. The system additionally includes an ultrasound transducer for locating and identifying one or more characteristics of the biomarker sensitive hydrogel and a computer system in electrical communication with the ultrasound transducer. The computer system is configured to receive characteristics of the biomarker sensitive hydrogel from the ultrasound transducer and determine dimensional changes of the biomarker sensitive hydrogel based on the received characteristics.